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  • J-Link debug probes
  • J-Link PLUS

    J-Link PLUS
    The JTAG/SWD debug probe with USB interface

    Based on a 32-bit RISC CPU, SEGGER's J-Link PLUS can communicate at high speed with the supported target CPUs.

    J-Link PLUS is available in two form factors with identical function: J-Link PLUS Classic and J-Link PLUS Compact.

    Buy now
    Compare J-Link models
    Documentation
    SEGGER J-Link PLUS + PLUS Compact debug probe
    1. 1.Key features
    2. 2.Supported devices
    3. 3.Software
      1. 3.1.Multi-platform
      2. 3.2.J-Flash
    4. 4.Flash Breakpoints
    5. 5.Ozone — The J-Link Debugger
      1. 5.1.Standalone debugger
      2. 5.2.Performance analyzer
    6. 6.Media gallery
      1. 6.1.Product photos
      2. 6.2.Videos
    7. 7.Technical specifications
      1. 7.1.Assembly dimensions
    8. 8.Package content
      1. 8.1.J-Link PLUS Classic
      2. 8.2.J-Link PLUS Compact
    9. 9.FAQ
    10. 10.Latest news

    Overview

    J-Link PLUS is a USB-powered JTAG debug probe supporting a large number of CPU cores. Based on a 32-bit RISC CPU, it can communicate at high speed with the supported target CPUs. J-Link is used around the world in tens of thousands of places for development and production (flash programming) purposes.

    The J-Link debug probes are supported by all major IDEs including Eclipse, GDB-based IDEs and SEGGER Embedded Studio. For a complete list, please refer to supported IDEs. Including all models, more than 500,000 J-Links have been shipped so far, making J-Link probably the most popular debug probe for Arm cores and the de-facto standard.

    Key features

    • Download speed up to 1 MB/s
    • Unlimited breakpoints in flash memory (Flash Breakpoints)
    • Use with Ozone, RDI / RDDI and J-Flash
    • Built-in VCOM functionality
    • Supports a broad range of microcontrollers
    • Supports direct download into RAM and flash memory
    • Free software updates

    Supported devices

    The J-Link PLUS as a member of the SEGGER J-Link debug probes supports a wide range of CPU cores. The list of supported manufacturers, families, and devices and SoCs includes tens of thousands of devices in hundreds of device families.

    Device not listed? Please don’t hesitate to contact us.

    SEGGER Flasher PRO - Icon: Three black puzzle pieces above blue puzzle piece (Universal Target Support)

    Software

    All software is included free of charge. It comes with licenses for all J-Link related SEGGER software products, such as J-Link Unlimited Flash Breakpoints, Ozone, RDI/RDDI, J-Flash, J-Link GDB Server, providing the optimum debugging solution for professional developers.

    J-Link PLUS can be used with almost all Arm debuggers, enabling download to flash memory with an unlimited number of breakpoints when debugging programs located in flash memory of most popular Arm microcontrollers. It also comes with the license to use J-Flash, SEGGER's popular flash programming software.

    The J-Link Software and Documentation Package is available here:

    DownloadJ-Link Software and Documentation Pack

    Multi-platform

    As a multi-platform solution, J-Link PLUS comes with the setup and control software for Linux, macOS and Windows. Software and firmware updates are included. Similarly, use on all currently supported target devices, and any that will be added, is also included.

    J-Flash

    J-Flash is part of the J-Link Software and Documentation Package and allows the programming of the internal and external flash memory of a microcontroller-based embedded system via J-Link.

    Learn more about J-Flash...

    J-Link PLUS: J-Flash (icon)

    Flash Breakpoints

    The J-Link PLUS comes with an additional feature, called Unlimited Flash Breakpoints. Unlimited Flash Breakpoints allow the user to set an unlimited number of breakpoints when debugging in flash memory.

    Learn more about Unlimited Flash Breakpoints...

    J-Link PLUS: Flash Breakpoints (icon)

    Ozone — The J-Link Debugger

    Ozone is the debugger for J-Link and J-Trace. It includes all well-known debug controls and information windows, and makes use of the best performance of J-Link and J-Trace debug probes.

    Standalone debugger

    Ozone focuses on debugging, with no compiler or project window distractions. All debug windows can be moved, resized and docked, to provide you with the workspace you need.

    Ozone offers all well-known debug controls and information windows, and more. Instruction trace, power graph, live watches, and real-time terminal I/O further extend these capabilities.

    Ozone: Debugging features (screen)
    Debugging with Ozone

    Performance analyzer

    With J-Link's High-Speed Sampling technology, Ozone can sample and visualize an embedded system's variables over time. Checking values and flags in the debugger is easy, while the target keeps running.

    J-Link's power measurement features enable you to record the power consumption of your target device in a debug session. This is especially helpful when you develop a low-power device and need to know how power consumption changes when you enable or disable certain components.

    Ozone: Performance analysis features (screen)
    Performance analysis with Ozone

    Media gallery

    Product photos

    SEGGER J-Link PLUS debug probe
    J-Link PLUS Classic front
    J-Link PLUS Classic host connector
    SEGGER J-Link PLUS Classic target connector
    J-Link PLUS Classic target connector
    SEGGER J-Link PLUS Compact debug probe
    J-Link PLUS Compact front
    SEGGER J-Link Compact debug probe host connector
    J-Link PLUS Compact host connector
    SEGGER J-Link PLUS Compact target connector
    J-Link PLUS Compact target connector

    Videos

    SEGGER J-Link Tutorials: The J-Link Configurator

    Mar. 2022 | 5:24 min
    J-Link — J-Link Configurator

    SEGGER J-Link Tutorials: The J-Link Commander

    Mar. 2022 | 7:48 min
    J-Link — J-Link Commander

    SEGGER J-Link Remote Server: Accessing a J-Link, J-Trace or Flasher remotely - anywhere in the world

    Mar. 2019 | 4:35 min
    J-Link Remote Server — Intro

    Jan. 2022 | 4:02 min
    J-Link — Performance analysis

    An introduction to Cortex-M faults and how SEGGER's Ozone debugger can help

    Aug. 2020 | 5:22 min
    J-Link & Ozone — Intro Cortex-M Faults

    Analyzing Cortex-M faults using SEGGER's Ozone debugger

    Aug. 2020 | 7:30 min
    J-Link & Ozone — Cortex-M Faults analysis

    SEGGER BBC micro:bit J-Link upgrade: Step-by-step instructions

    Aug. 2016 | 1:33 min
    BBC micro:bit J-Link Upgrade — Intro

       View more...

    Technical specifications

    General
    Supported OSMicrosoft Windows (x86/x64), Linux (x86/x64/Arm), macOS (x86/Apple Silicon)
    Electromagnetic compatibility (EMC)EN 55022, EN 55024
    Operating temperature+5°C ... +60°C
    Storage temperature-20°C ... +65 °C
    Relative humidity (non-condensing)Max. 90% rH
    Mechanical
    Size of J-Link PLUS Classic (without cables)100mm x 53mm x 27mm
    Weight of J-Link PLUS Classic (without cables)70g
    Size of J-Link PLUS Compact (without cables)46mm x 46mm x 17mm
    Weight of J-Link PLUS Compact (without cables)20g
    Available Interfaces
    USB interface (J-Link PLUS Classic)USB 2.0 (Hi-Speed); USB Type B
    USB interface (J-Link PLUS Compact)USB 2.0 (Hi-Speed); USB-C
    Target interfaceJTAG/SWD 20-pin (adapters available)
    JTAG/SWD Interface, Electrical
    Power supplyUSB-powered Max. 50mA + Target Supply current.
    Target interface voltage (VIF)1.2V ... 5V
    Current drawn from target voltage sense pin (VTRef)< 25µA
    Target supply voltage5V (derived from USB voltage)
    Target supply currentMax. 300mA
    Reset typeOpen drain with 100 Ohms series resistor. Can be pulled low or tristated
    Reset low level output voltage (VOL)VOL <= 10% of VIF
    For the whole target voltage range (1.2V <= VIF <= 5V)
    LOW level input voltage (VIL)VIL <= 40% of VIF
    HIGH level input voltage (VIH)VIH >= 60% of VIF
    For 1.2V >= VIF <= 3.6V
    LOW level output voltage (VOL) with a load of 10 kOhmVOL <= 20% of VIF
    HIGH level output voltage (VOH) with a load of 10 kOhmVOH >= 80% of VIF
    For 3.6 <= VIF <= 5V
    LOW level output voltage (VOL) with a load of 10 kOhmVOL <= 20% of VIF
    HIGH level output voltage (VOH) with a load of 10 kOhmVOH >= 80% of VIF
    JTAG/SWD Interface, Timing
    Target interface speedMax. 15 MHz
    SWO sampling frequencyMax. 30 MHz
    Data input rise time (Trdi)Tfdi <= 20ns
    Data output rise time (Trdo)Trdo <= 10ns
    Data output fall time (Tfdo)Tfdo <= 10ns
    Clock rise time (Trc)Trc <= 3ns
    Clock fall time (Tfc)Trc <= 3ns

    Assembly dimensions

    The compact variant of the J-Link PLUS is designed to mount securely and unobtrusively into development or end user equipment. The small size and two mounting holes enable placing the J-Link PLUS Compact into existing equipment housings or to reserve space for direct-to-PCB mounting.

    Typical applications are test fixtures that are used to automate firmware verification during development, or long-term test setups. It also can be used for integrated firmware reflash or service purposes inside end equipment, minimizing the number of tools that service technicians must carry around.

    Download PCB 3D-STEP data

    Download PCB dimensions

    J-Link PLUS compact assembly
    Explosion view of the J-Link PLUS Compact
    J-Link Compact Dimensions
    Assembly dimensions of the J-Link PLUS Compact

    Package content

    J-Link PLUS Classic

    SEGGER J-Link PLUS debug probe
    J-Link PLUS Classic
    SEGGER Flasher PRO - Gray Cable Ribbon 20 pin shadow
    .1" 20-pin ribbon cable
    Black Cable USB shadow
    USB cable

    J-Link PLUS Compact

    SEGGER J-Link PLUS Compact debug probe
    J-Link PLUS Compact
    SEGGER Flasher PRO - Gray Cable Ribbon 20 pin shadow
    .1" 20-pin ribbon cable
    Product picture USB-C cable black
    USB-C cable

    FAQ

    Q: Can I use J-Flash with J-Link PLUS?

    A:  Yes. J-Link PLUS comes with a license for J-Flash preinstalled on the probe itself. No license setup necessary, simply plug in J-Link PLUS and start using J-Flash.

    Q: What is the advantage of J-Link versus simple probes such as FTDI-based systems?

    A:  J-Link has numerous advantages: the actual J-Link software supplied by SEGGER (which enables use with common IDEs), the availability of Unlimited Flash Breakpoints for the debugging of software which runs in the flash of microcontrollers, it’s high speed and it’s simple, fast download into flash memory.

    In contrast to most simple probes, J-Link supports adaptive clocking as well as SWD and SWO. It also functions more stably, since it is not just a dump USB to JTAG converter. Instead, it uses the intelligence of the built-in CPU which provides more robust communication. This is especially so in situations where the target CPU runs at low clock speeds.

    Q: May I work with more than one J-Link at the same time, on the same machine?

    A:  Yes, you can connect an unlimited number of J-Links to your PC. No special configuration required; each J-Link is registered with its unique serial number on the PC. This enables you to have multiple J-Links connected at once.

    Q: I have multiple Arm cores in my JTAG chain. How can I debug them (simultaneously) with J-Link?

    A:  That's simple: Two or more debuggers can use the same J-Link simultaneously. Multi-core debugging requires multiple debuggers or multiple instances of the same debugger. You need to tell your debugger which device in the scan chain you want to debug. Additional special settings are not required.

    Q: Does J-Link support the Embedded Trace Buffer (ETB)?

    A:  Yes. J-Link supports ETB on Cortex-M3/M4/M7 and Cortex-A/R (if implemented by target device).

    Q: Does J-Link support the  Micro Trace Buffer (MTB)?

    A:  Yes.

    Q: Does J-Link support the Embedded Trace Macrocell (ETM)?

    A:  No. ETM requires another connection to the ARM chip and a CPU with built-in ETM. ETM is supported by the J-Trace product family.


    Latest news

    2025
    Sep.04
    J-Link
    SEGGER and Winbond logos with handshake graphic

    SEGGER establishes programming-support partnership with Winbond Electronics Corporation

    Effective immediately, SEGGER programming support is available for selected SPI flash-memory devices from Winbond Electronics Corporation. SEGGER's highly regarded J-Link and Flasher product lines are now fully compatible with Winbond's high-performance W25H, W25Q, and W25X SpiFlash® multi-input/-output (I/O) serial-flash-memory-unit families.

    [Read more...]

    All news

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